Last weekend's Pokemon Go Fest in Chicago did not go as planned, largely because many attendees found themselves unable to actually play Pokemon Go on site. Developer Niantic was quick to promise refunds, in-game currency and a free legendary Pokemon to all attendees, but it took a little time in explaining what exactly went wrong.

Niantic CEO John Hanke clarified those details in a blog post yesterday, splitting the blame between his own company and an array of unnamed network service providers. On Niantic's side, Hanke said there were technical issues crashing the game for some users, but those were largely addressed by a server configuration change. The "more protracted problem," according to the blog post, was congested mobile data networks.

"On the pure network access issue, we provided detailed estimates on attendance and required data throughput per user to our event partner who worked with the major carriers to allow them to plan for adequate coverage," Hanke said. "Some carriers deployed Cellular on Wheels (COWs) to extend their capacity. In other cases the providers deemed them unnecessary based on other infrastructure already in place at the site. Users reported different levels of success with these providers. Wifi was enabled by one provider as a solution which helped some users but not all. Sprint was onsite as an official partner, deployed a COW, and their network was busy but held up well."

Despite the difficulties experienced with Pokemon Go Fest, Hanke also said the company has no intention of dropping plans for live events in the future.

"Real-world events are core to the Niantic mission of exploration, exercise and social interaction," Hanke said. "We've been doing events since the early days of Ingress in 2012. Those events grew progressively larger over time, starting with a few dozen attendees and growing to over 10,000 in Tokyo last summer. At each stage of growth, we encountered challenges and each time we overcame them, we gained new skills and pioneered new techniques for building real-world experiences that support our mission. Last Saturday was not a happy day for us but we are committed to listening to that feedback, however harsh, to improve what we do so that we can continue to build experiences that bring together people, technology, and the real world in innovative ways."

Hanke added that the lessons from Pokemon Go Fest will be put to use later this summer in Pokemon Go events across Europe and in Yokohama, Japan.

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